packagessymbols
Here is what I did:
ifsym package from MiKTeX Package Manager. (MPM)I added the line to my .tex file:
\usepackage{ifsym}
I tried typing \Letter in the document.
but it doesn't work.
The \Letter is a symbol in ifsym package if I know correctly, which looks like an envelope.
Do I miss something?
You should load fontspec with the no-math option.
\documentclass[11pt]{article}
\usepackage{amsmath}
\usepackage[no-math]{fontspec}
\setmainfont{STIX}
\usepackage{stix}
\begin{document}
\begin{equation*}
\Omega=\lbrace O:l_o=1,C:l_o=0,B:0<l_o<1 \rbrace
\end{equation*}
\end{document}
Here's a possible solution working in all sizes.
\documentclass{article}
\usepackage{amsmath}
\usepackage{etoolbox}
% fix amsmath's \dddot
\patchcmd{\dddot}{#1}{\kern0pt #1}{}{}
\makeatletter
\DeclareRobustCommand{\barredI}{%
\mathord{\vphantom{I}\mathpalette\@barredI\relax}%
}
\newcommand{\@barredI}[2]{%
\ooalign{%
\hidewidth\@barredIbar#1\hidewidth\cr
$\m@th#1I$\cr
}%
}
\newcommand{\@barredIbar}[1]{%
\check@mathfonts
\ifx#1\displaystyle
\fontsize{\f@size}{\z@}%
\def\@barredIbarkern{0.3}%
\else
\ifx#1\textstyle
\fontsize{\f@size}{\z@}
\def\@barredIbarkern{0.3}%
\else
\ifx#1\scriptstyle
\fontsize{\sf@size}{\z@}
\def\@barredIbarkern{0.4}%
\else
\fontsize{\ssf@size}{\z@}
\def\@barredIbarkern{0.47}%
\fi
\fi
\fi
\usefont{OT1}{cmr}{m}{n}%
\kern-\@barredIbarkern em
\raisebox{-.5ex}{\symbol{'26}}%
}
\makeatother
\begin{document}
$\barredI_{\barredI_{\barredI}}$ $I\barredI$
\bigskip
$\dddot{I}_{\!jk}\dddot{\barredI}_{\!jk}$
\end{document}
Best Answer
You need to use
since this symbol is only defined when using the
miscpackage option.